The agency scooped the account in a final-round contest against MediaCom and incumbent Zenith Media in a pitch overseen by the AAR.
Initiative Media, Walker Media and Carat were eliminated at an earlier stage. Zenith has held the account since 1998.
The appointment results from a review triggered by BT's head of media Grant Millar. BT previously had to conduct a statutory review of its media account via the Official Journal of the European Community but these rules were relaxed recently, allowing it to review as the need arises.
Media planning continues to be handled by PHD while The Allmond Partnership is responsible for television buying. The appointment comes amid a £33m advertising assault by the company to promote BT Broadband.
The telecoms giant is also currently on the hunt for a third creative roster agency to function as an ideas shop, working alongside St Luke's and Abbott Mead Vickers BBDO. Pitches are expected to take place in the new year.
Millar was unavailable for comment at the time of publication.
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